Centrifugal apparatus



July 2, 1940. w. HOFFMAN CENTRIFUGAL APPARATUS Filed April 19, 1938 2 Sheets-Sheet l 32. 1 ATTORNEYS INVENTOR WALTER HOFFMAN BY July 2, 1940. w. HOFFMAN CENTRIFUGAL APPARATUS Filed April 19, 1938 2 Shee'ts-Shaet 2 INVENTOR WALTER HOFFMAN ATTORNEYS Patented July 2, 1940 PATENT OFFICE 2,206,401 cmarr'uosr. maaa'ms Walter Hoffman, Hamilton, Ohio, assignor to The Western States Machine Company, New York, N. Y., a corporation of Utah Application April 19, 1938, Serial No. 202,960

llclaims.

This invention relates to centrifugal apparatus of the type employed in the recovery of grain sugar from mixtures of sugar crystals and syrup and for like purposes. It deals particularly with such apparatus embodying new and improved means for protecting the contents of the centrifugai basket against the objectionable cooling and drying effects of strong air currents and against contamination by foreign matter during centrifuging operations.

When purging sugar massecuites in the usualopen top centrifugals, especially if the treatment must be prolonged in order to eflect properseparation of the molasses, as in the case of highly viscous low grade massecuites, or if the centrifugals are operated at very high speeds, the air currents created by revolution of the basket materially reduce the temperature of the material and also cause appreciable drying of the unseparated molasses. A drop of a few degrees in the temperature of saturated molasses results in a great increase in its viscosity and often is attended by the formation of objectionable "false grain," or discrete sugar crystals, which interfere seriously with the efllciency of separation. Drying of the massecuite also is harmful, since it increases viscosity and thus reduces the quality of separation. In addition to these considerations, it is always important, particularly in the purging of refined sugar massecuites, carefully to exclude foreign matter from the contents of the centrifugal basket. The possibility of water, dust, grit or other matter entering the loaded basket and contaminating the sugar is generally present wherever centrifugal apparatus is used.

A further problem encountered in the operation of the usual type of centrifugal at very high speeds consists in the sweeping of strong air currents from the open top of the curb through and around the basket and through the bottom discharge outlet of the curb where these currents exert an objectionable blowing action and cause difficulties in the handling of sugar discharged from the centrifugal.

An object of my invention is to provide centrifugal apparatus embodying new and improved means for covering the top 'of the curb during a purging'operation, so that the contents of the basket are protected against the harmful effects of strong air circulation and kept free of contamination by foreign matter during ceninfusing operations, and so that the objectionable windage below the curb may be avoided. I have provided apparatus of this type which effectively eliminates these objectionable features of the usual open top centrifugal, and which in no way interferes with or requires modification of operations customarily carried out duringthe centrifuging cycle. My improved apparatus is further advantageous in that it is organized to 5 permit easy manipulation by the attendant of the centrifugal without interference with his other du ies. I

Another object of my invention is to provide a new and improved centrifugal curb top cover 0 which is constructed and arranged in combination with a centrifugal, a surrounding curb and the units of equipment normally associated therewithsuch as discharger, sprayer, loading chute and basket valve support-so that the cover may 15 be mounted permanently on the curb top Wt moved easily to and from open position allowing full access to the basket for the loading and discharging operations without obstruction by any of said units.

Additional novel features and advantages of the invention and a desirable manner of applying it in practice will be apparent from the ensuing description when considered in connection with the illustrations on the accompanying drawings. It will be understood, of course, that the invention is not restricted to the details of construction and arrangement shown in the drawlngs, but extends also to other embodiments utilizing novel features of the invention as set forth in the claims appended hereto;

In the drawings,

Figure 1 is a plan view of a centrifugal curb top and associated units provided with an improved curb top cover in accordance with my invention, the cover being shown in closed position. The phantom lines in this figure indicate the position of the usual loading chute and control gate overlying the curb.

Figure 2 is a vertical section taken approxio mately along the lines 2-2 of Figure 1.

Figure 3 is a plan view similar to Figure l, with the curb top cover in open position and other units of the apparatus in position for discharging material from the centrifugal basket, and

Figure 4 is a vertical section taken approximately along the lines 4-4 of Figure 3.

The drawings show a form of curb top cover provided in accordance with this invention in operative association with the curb top of a suspended centrifugal and other units of equipment employed in the operation of the centrifugal. The curb ill surrounds a perforate -centrifugal basket it, which is suspended on a vertical spindle It and adapted to be revolved at high speed 55 to effect separation of liquid and solid materials introduced into the basket. The curb has a circular top wall It, with a central opening I. therein permitting access to the basket. The front of the apparatus and the approximate position normally occupied by the attendant operatingthe centrifugal is indicated by the character Ain Figures 1 and 3. Considerably to the right of this position is located a control arm ill of a gate normally lying across a loading chute 22, which chute overlies the curb top in position to direct material from the end of the chute through the opening it and into basket I! when arm 20 is actuated to open the control gate and permit material to fiow through the chute. A discharger unit is mounted on the curb top a few degrees to the left of the position A. This unit usually comprises a vertically movable spindle 24 carrying a discharger shoe 2. on its lower end and mounted in a bracket 28 which overhangs the curb opening it in a manner permitting the discharger shoe and spindle to be lowered into the basket through the opening. The discharger is provided with mechanism for swinging the spindle and shoe about the vertical axis of the spindle. when the discharger is not in use the shoe 28 rests on supporting means in the form of a bracket 29 having an end portion secured to the curb top and another end portion extending over the opening ll and spaced above the plane of the curb top substantially as shown in Figures 1 and 2. When the discharger is to be used, it is swung horizontally to a positionover the openin L8 and free of the bracket 29, lowered vertically into the basket and then moved clockwise about its axis and pressed into the wall of material inside the basket.

In addition tothe loading chute and discharger, the illustrated apparatus includes a sprayer a for directing a spray into the material inside the basket during a. centrifuging cycle.

It also includes means M for supporting a bottom Hook I4 is positioned below thecurb top in such relation to the discharger that the bottom closure k. may be raised and engaged .on the hook by means of an eye 32 without obstructing the path of movement of the discharger shoe as the latter is lowered into the basket and manipulated The sprayer I8 is mounted ontheourb top in a position between the'loading chute and dis-, charger and toward the back side of the curb,

means such as indicated at 40 serving for this.

purpose. The sprayer extends below the curb top in position to direct a spray across unobstructed space between the peripheral wall of the basket charger and sprayer,fmay be of any suitable known construction. As individual units of;

eduipment'they do not constitute novel features 7 of the present invention. In .accordancewith this invention, I have proyidsd-a new and improved curb top cover in comclosing the opening I. and preventing objectionable air currents and foreign matter from entering the curb to an open position exposing the opening I! and permitting free access to the basket I! so that a charge may be introduced into the basket and treated material discharged therefrom in the usual manner. The curb top cover is constructed and arranged with reference to the other units of apparatus associated with the curb so that its sections are unobstructed in moving back and forth from closed to open position in the normal operation of the centrifugal. In addition, it-is arranged in a manner permitting the attendant of the centrifugal'to cover or expose the opening it by a single simple manipulation which may be performed easily and without complicating or-prolonging the attention normally required by the centrifugal apparatus during each complete cycle of operation.

In a preferred form of my invention, as illustrated in the drawings, the curb top cover comprises two relatively movable sections ill and 52 which are of a size and shape adapted to fit together in closed position and substantially cover the opening I8 in the curb top and to move freely to open position exposing the opening without interference by the sprayer, discharger or loading chute.

Sections 50 and 52 closely overlie the curb top i6 as indicated in Figures 2 and 4. Each section is mounted for swinging movement in a horizontal plane about a fixed axis lying beyond the margin of opening I. and on normally unused portions of the curb top. Suitable mountingmeans include bars 54 and 55, which are rigidly secured to the respective sections and swiveled at their ends to the curb top by pivots 58 and 60, respectively. In the illustrated embodiment, the curb top I6 is provided with an integral portion 62 extending inwardly toward the spindle I4 from the back side of the curb between the discharger and load-chute. The edges of this inwardly extending portion 52 define side margins of opening l8, which otherwisewould be circular.- 'Ihe sprayer ll is mounted to extend over portion 61 and downwardly through an opening therein into position below the curb top for directing a spray into the contents of the basket. To the bottom of portion "is secured the mounting bar for the la ook support 34, as indicated in Figures 1 and The cooperating. cover sections and Rare preferably of sector-like configuration, one cover ing an arc of at least and the other an are I of less than 180 and the two together in closed position having margins which overlie the -margins of opening ll, including the edges of portion 82, and substantially cover the entire opening. Sections 50 and-52 have central recessedportions which, when the sections lie in closed position, providecentral apertures 66 and II, the first permitting requisite swinging move-I ment of the basket spindle I l and the second permitting inspection" of the hook support 34 to determine, whether the .basket closure III is supported by the hook or ioweredintoclosed position inwthebottomof the-basket. Aperture" valso would permitlthe hook 34 to be suspended on means extending from'a'bove to the indicated position below-the curb top. n

In the illustrated organisatiomsection II is:

the larger of the two cover sections, and section I! the smaller. The pivot 58 forming the axis for section 50 is located on the curb top adjacent but in clockwise displacement from the sprayer mounting 40, so that in swinging to open position about pivot 58 section 50 moves in a direction away from the discharger and in a path extending beneath the loading chute 22 overlying the curb top. The pivot 80 for section 52 is fixed on the curb top between the discharger and sprayer mounting so that section 52 swings away from opening ii in a path lying between the discharger and sprayer. 'Thus the paths of the sections in moving to or from open position and their location when in open position occupy otherwise unused portions of the curb top and do not interfere with normal operation of the apparatus.

In addition to the features mentioned above, my improved curb top cover construction provides a plurality of relatively movable sections together with means responsive to the movement of one of the sections to or from closed position to move the other to and from closed position. For example, means such as a link 10 extends between the two sections and is connected to each by swivels or pivots l2 and 14, respectively. These pivots both lie to one side of the pivots I8 and 60 and are arranged so that the movement of sec tion 50 around its pivot 58 exerts a force upon section 52 through link 10 causing section 52 to swing about its pivot 60. By this means the operation of closing or opening the curb top may be carried out by a single, simple manipulation. To facilitate this manipulation, a handle 80 is mounted on section 50 adjacent the front of the curb.

In the normal cycle of operation of the described apparatus, assuming the centrifugal basket to be empty, the discharger shoe resting on the supporting means 29, and the curb top cover in closed position, the attendant of the machine first moves handle 80 in a counterclockwise direction and thus shifts the cover sections to open position fully exposing the opening i8. He then grasps a handle on the gate control lever and actuates the same to introduce a charge of material into the basket, which, during this stage of operation, is revolved at .a relatively low speed. After dropping the gate to close the loading chute, the attendant again grasps handle 80 and shifts the cover sections to closed position, whereupon the centrifugal is ready for the purging operation. With the cover in closed position revolution of the basket at high speed takes place without dimculties due to air currents entering the curb through the curb top or to the inadvertent introduction of foreign matter into the basket. During the spinning operations a washing agent may be directed into the basket from sprayer 38 in the usual manner. After the charge has been treated to the desired extent, the centrifugal is decelerated, and is then in condition for discharging. Thereupon the attendant again shifts the curb top cover to open position, raises the bottom closure 30 and supports it on member 34, and then swings the dis-' charger shoe 26 from its position on bracket 29 to a free position over opening it and lowers the discharger into the basket. The discharging operation is carried out in the usual manner. The bottom closure 30 is then disengaged from support 3|, placed back in normal position, and the machine again loaded with another charge of material from loading chute 22.

While I have illustrated a preferred embodiment of my invention in combination with centrii'ugal apparatus of the suspended type having numerous accessory units associated therewith, it is to be understood that the invention is not restricted to this particular arrangement or to the illustrated details of construction. I intend that the invention be given a scope commensurate with its novel contributions as limited only by, fair interpretation of the claims.

I claim:

l. A centrifugal-curb top cover comprising two relatively movable sections adapted in closed position tocover the opening in a centrifugal curb top, means mounting said sections for swinging movement about spaced vertical axes lying outside the margins of said opening and means connecting said sections together and responsive to .movement of one of said sections in a counterclockwise direction about its axis to move the other section in a counterclockwise direction about its axis and thus to expose said opening.

2. A centrifugal curb top cover comprising two relatively movable sector-like sections overlying the centrifugal curb top and adapted in closed position to cover the opening in a centrifugal curb top, means mounting said sections for swinging movement about spaced vertical axes lying outside the margins of said opening and link means connecting said sections together and responsive to movement of one of said sections in a counterclockwise direction about its axis to move the other section in a counterclockwise direction about its axis and thus to expose the opening.

3. A centrifugal curb top cover comprising a plurality of relatively movable sections including two dissimilar movable sections adapted in closed position to cover the opening in a centrifugal curb top, means mounting said 'movable sections for horizontal movement away from said opening to positions overlying saidcurb top, and link means connecting said movable sections together and responsive to movement of one of said. movable sections away from closed position to move the other and expose said opening.

4. In combination with a centrifugal and a surrounding curb having an opening in its top wall permitting access to the centrifugal basket, a curb top cover comprising two dissimilar cooperating movable sections adapted in closed position to cover said opening, means mounting said sections for movement about fixed vertical axes to and from closed position, link means connecting said sections and responsive to movement of one of them to or from closed position to move the other to or from closed position, and a handle on said one section for moving the same to and from closed position.

5. In combination with a suspended centrifugal and a surrounding curb having an opening in its top wall providing space for access to the basket between'the basket spindle and said wall, a curb top cover comprising two dissimilar cooperating sector-like sections movable from closed position covering said opening to open position exposing the same, one of said sections covering an are greater than the other and the two in closed position forming a substantially circular closure having outside margins which overlap the margin of said opening and inside margins which embrace said spindle and provide a small space ,around' the spindle permitting swaying of the same, means mounting each of said sections for horizontal movement to and from closed position about a fixed axis lying outside the margin of said opening. and means responsive to movement of one of said sections about its fixed axis to move the other about its iixed axis.

6. In combination with a suspended centrifugal and a surrounding curb having a circular top wall with a central opening therein surrounding the spindle and permitting access to the basket, a curb top cover comprising two coopersting sector-like sections movable from closed position across said opening to open position exposing the same, one of said sections covering an arc of at least 180, the other an'arc of less than 180 and the two in closed position forming an incomplete circle having a central aperture accommodating the spindle, said top wall having a stationary portion extending toward the spindle to a position underlying free edges of said sections, and means mounting each of said sections for swinging movement away from said opening.

'7. In combination with a centrifugal and a surrounding curb having an opening in its top wall permitting access to the centrifugal basket, a curb top cover comprising a plurality of movable cooperating sections, an arm fixed to each of said sections and extending over said curb top, swivel means connecting said arms to the curb top at spaced points permitting said sections to swing together about the points of connection to closed positions covering said opening and to swing apart to positions exposing the same, and link means connecting said sections together and swiveled to each section and responsive to movement of one section to or from closed position to move the other to or from closed position.

8. In combination, a circular curb top for a suspended gyratory centrifugal, said top having a portion extendinginwardly toward its center and an otherwise substantially circular opening adapted to surround the spindle of a centrifugal and to permit the introduction of material into and the operationof a dischargerinside the besket, and a curb top cover comprising two cooperating sector-like sections movable from closed pomtion substantially covering saidopening to open position exposingthe same, one of said sections covering at least 180 and the other substantially less than 180", means mounting'said one section for swinging movement about a pivot on said top in a path extending away from-said portion and means mounting said other section for swinging movement about another pivot on said top and in a path lying between its pivot and said one section.

9. In combination, a circular .curb top for a suspended gyratory centrifugal, said tophaving a portion extending inwardly toward its center and an otherwise substantially circular opening adapted to surround the spindle of a centrifugal and to permit the introduction of material into and the operation of a discharger inside the hasket, and a curb top cover comprising twocooperw from open position.

ating sector-like sections movable from closed position substantially covering said opening to open position exposing the same, one of said sections covering at least 180 and the other substantially less than 180, means mounting said one section for swinging movement about a pivot on said top in a path extending away from said portion, means mounting said other section for swinging movement about another pivot on said top and in a path lying between its pivot and said one section, a link extending between said sections and swiveled to each at points located to top wall and adapted to be supported on said top wall outside of said opening when not in use and to be lowered into the basket through said openingfor use, a sprayer mounted on said top wall away from said discharger and extending below the wall to a position within the basket, a curb top cover comprising a plurality of cooperating sections movable from closed position embracing said spindle and covering said opening to open position overlying said top wall and exposing said opening, and means mounting said sections for horizontal movement to open position in paths free of said discharger and sprayer.

11. ,In combination, a suspended centrifugal, a surrounding curb having an opening in its top wall surrounding the spindle and permitting access to the basket, a" discharger mounted on said top wall and adapted to be supported on said top wall outside of said opening when not in use and to be lowered into the basket through said opening for use, said wall-having a stationary portion extending-inwardly toward the spindle, a sprayermounted on said wall away from said discharger and extending downwardly through said portion to a position within the basket, a

support upon-which to suspend the bottom clos-- ure of the, basket, means extending from said wall portion to hold said support adjacent the spindle and between the same and the discharger,-a

curb top cover comprising a plurality of cooper-.-

ating sections movable from closed position covering said opening to open position overlying said top wall and exposing said opening,

said sections in closed position providing apertures permitting swaying of the'spindle and inspection of said support, means mounting said sections for swinging movement to open position in substantially horizontal paths free of said discharger and sprayer, and means connecting said sections for simultaneous movement to and WALTER mm. 1 

